Reinstalling Windows - How do I DEFINITELY wipe off all viruses?

Discussion in 'Windows 7 Installation' started by shiphen, Jan 12, 2010.

  1. shiphen

    shiphen Well-Known Member

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    How do I wipe clean my Windows 7 hard disk?
    My current installation had problems with viruses and I need to re-install Windows7.
    And what size should I make the partitions?

    I have a 500GB hard disk.
    I tried booting off a DVD, but when it says "Where do you want to install windows?" the Format option is suspiciously fast (it seems to happen in about 3 seconds!) . So how do I completely wipe clean all trace of all files in the existing installation?

    Ship
     
  2. kemical

    kemical Windows Forum Admin
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    If you want to do whats called 'zeroing' the HD (basically filling the harddrive with zero's) then you can use something like this app:

    Active@ Kill Disk Hard Drive Eraser. Low Level Format.

    It can take some time to complete so be prepared for the wait. Once done you can then boot from DVD again and install windows. As for partition size, it depends on what you want? You could either leave it at 500GB and create a partition later using 'Disk management' or split the drive in two and have two partitions of 250GB.
     
  3. shiphen

    shiphen Well-Known Member

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    Thanks Kemical.
    I dont really want to wait more than an hour or two. (Time is money!)
    Do you feel that I am just being paranoid about virus files getting through a re-installation of Windows 7 ?

    Regarding partition size I am completely confused. I have no idea how many partitions I want or what the issues are - (although FWIW, I did read some theory that a small partition might force itself onto the outside of the hard disk and thus run faster!).

    Worse, the dialogue called "Where do you want to install Windows?" is extremely clunky. And if you click on Advanced options, you get the chance to: delete, format, new, extend, load driver, refresh. So I have deleted all the partitions, but when I created a new partition, windows7 insisted on creating its own partition called "System Reserved" (100MB with 86MB free).

    Do I need to create more partitions? What are the issues? (e.g. Can I readily change partition sizes later?)
     
  4. kemical

    kemical Windows Forum Admin
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    The normal format should be fine really.. Although why not run something like Microsofts security essentials before you re-install?

    As for the 100MB partition, thats created by default and is needed for certain files. You can get round the 100mb partition by formating the drive yourself but to be honest I wouldn't worry about it.
    You can create further partitions at a later date if need be by using disk management..
     
  5. TechieJustin

    TechieJustin New Member

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    I'd like to jump in here real quick.
    I have seen malware, spyware and virus infections where even after AV programs are run and the system is reported as "clean" there are stability and speed issues. IMO those programs leave "holes" and the installation is never the same.
    There are other times where I have deleted partitions via the Windows install CD/DVD and come up with two options to boot - e.g. Windows XP Professional and Windows XP Professional. Somehow despite blowing away all partitions something was left behind by the previous Windows install.

    I use a utility called DBAN - Darik's Boot and Nuke. It can be used to zero out the drive or perform a Department of Defense style wipe - if you want to sell the hard drive on eBay for example. I generally use the zero out option. Then when Windows goes to format the drive, I don't choose the quick format I chose the long - just to make sure the filesystem is in top shape. I guess I'm paranoid.
     
  6. kemical

    kemical Windows Forum Admin
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    Agreed... zeroing the disk is the only way to make sure and if you don't want to sit there and wait, do it over night.
     

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